The invention relates to pneumatic boats of the inflatable-deflatable type, capable of being propelled by motor: such boats comprise at least one inflatable member forming two parallel or substantially parallel arms which join up towards the front to form a stem-post, and a rear board which connects these two arms and may be equipped with at least one motor.
This motor may be added to the rear board or incorporated therewith.
By pneumatic boat of the inflatable-deflatable type is meant boats which may be presented in a navigating condition (inflated boat) or in a transporting condition or storing condition (deflated boat) as opposed to some types of boats which constitute flexible structures made rigid by inflation.
Up to the present, boats of this kind were provided with a floor having rigidity, at least in the transverse direction, a bottom canvas fixed on the lower part of the inflatable member and a rigid or inflatable keel interposed between this floor and this bottom canvas so as to give to the latter a "V" cross-section conferring on the boat its qualities of navigability (rapid lift, stability, speed).
Generally, when it is desired to propel such boats with more than 10 hp, it is necessary to arrange the floor so that it has, besides its rigidity in the transverse direction, rigidity in the longitudinal direction for transmitting the thrust exerted on the rear board by the motor(s) of the boat.
In practically all cases, the floor of these boats is formed from several elements which have rigidity in the transverse direction and must be joined by appropriate means so as to obtain rigidity in the longitudinal direction.
The result is therefore a boat having the disadvantage of relatively complicated and time-consuming assembly, which runs counter to the pneumatic character of the boat. Moreover, the floor accounts for a large part, of the order of 30% to 40%, of the weight of the boat because of the mechanical characteristics which the component elements of this floor and their assembling means must have in the longitudinal direction.